Volt Normals · VN-1

Climatology that admits the trend

The documented, persistent mispricing in weather markets is stale climatology: 10- and 30-year normals lag the warming trend — and the warm tails are fattening faster than the means. Volt Normals fit an exact quantile regression on year per station, per day-of-year, per quantile, and evaluate it at this year. Free to cite with attribution ("Volt Normals (Voltcast)" + link).

Today — trend-adjusted vs stale, °C

Full-year CSV, all stations →
Station Tmax normal (VN-1) Stale climatology Stale bias Q90 today Trend Q50 Trend Q90
EBBR Brussels Airport 23.8 23.5 +0.3 30.2 +0.12°C/dec +1.22°C/dec
EDDL Düsseldorf Flughafen 24.0 24.9 -0.9 31.0 0.00°C/dec 0.00°C/dec
EDDM München Flughafen 26.4 24.6 +1.8 31.0 +1.11°C/dec 0.00°C/dec
EETN Tallinn Lennart Meri 23.8 22.5 +1.3 27.0 +2.54°C/dec 0.00°C/dec
EFHK Helsinki-Vantaa 25.0 22.9 +2.1 28.7 +2.33°C/dec +0.20°C/dec
EGLC London City Airport 23.0 22.7 +0.3 29.2 0.00°C/dec +0.83°C/dec
EGLL London Heathrow 23.5 23.9 -0.4 30.3 -0.73°C/dec +0.33°C/dec
EHAM Amsterdam Schiphol 22.7 22.3 +0.4 28.7 +0.85°C/dec +0.50°C/dec
EIDW Dublin Airport 19.3 19.4 -0.1 23.8 -0.43°C/dec +0.25°C/dec
EKBI Billund Lufthavn 22.4 21.7 +0.7 28.5 +1.20°C/dec +1.18°C/dec
EKCH København Kastrup 22.2 21.8 +0.4 26.3 +1.38°C/dec 0.00°C/dec
ENBR Bergen Flesland 18.4 17.8 +0.6 25.9 +1.25°C/dec +1.75°C/dec
ENGM Oslo Gardermoen 21.8 21.5 +0.3 29.0 +1.00°C/dec +1.60°C/dec
ENTC Tromsø Langnes 18.7 15.5 +3.2 23.3 +4.30°C/dec +3.09°C/dec
ENVA Trondheim Værnes 22.0 19.3 +2.7 31.8 +3.45°C/dec +4.83°C/dec
ENZV Stavanger Sola 18.5 18.4 +0.1 25.1 +0.50°C/dec +0.33°C/dec
EPWA Warszawa-Okecie 26.7 25.0 +1.7 30.6 +2.00°C/dec +1.75°C/dec
ESMS Malmö Sturup 22.1 21.6 +0.5 27.0 +1.00°C/dec +0.42°C/dec
ESSA Stockholm-Arlanda 21.8 22.6 -0.8 27.1 -0.82°C/dec -1.40°C/dec
EVRA Rīga Airport 22.4 21.6 +0.8 26.8 +0.42°C/dec -0.14°C/dec
LBSF Sofia Airport 31.6 29.1 +2.5 36.3 +2.00°C/dec +1.54°C/dec
LDZA Zagreb Pleso 29.5 27.0 +2.5 33.0 +1.21°C/dec -1.43°C/dec
LEMD Madrid-Barajas 36.6 34.4 +2.2 41.0 +1.46°C/dec +3.12°C/dec
LFPB Paris-Le Bourget 25.8 25.7 +0.1 31.2 +0.17°C/dec +0.10°C/dec
LFPO Paris-Orly 26.2 26.2 0.0 32.1 0.00°C/dec +0.60°C/dec
LGAV Athens Eleftherios Venizelos 33.8 32.9 +0.9 38.3 +0.80°C/dec +1.82°C/dec
LHBP Budapest Liszt Ferenc 31.0 28.3 +2.7 35.2 +2.50°C/dec +2.14°C/dec
LIML Milano Linate 32.4 30.6 +1.8 34.8 +2.00°C/dec +0.86°C/dec
LIRF Roma Fiumicino 31.7 29.4 +2.3 34.5 +2.17°C/dec +2.33°C/dec
LJLJ Ljubljana Brnik 29.0 28.5 +0.5 31.9 0.00°C/dec -1.56°C/dec
LKPR Praha-Ruzyně 26.9 24.7 +2.2 30.7 +1.56°C/dec +0.38°C/dec
LOWW Wien-Schwechat 29.6 26.7 +2.9 34.2 +2.40°C/dec +2.09°C/dec
LPPT Lisboa Humberto Delgado 28.0 28.8 -0.8 34.7 0.00°C/dec +1.43°C/dec
LROP București Otopeni 33.8 30.5 +3.3 38.8 +2.92°C/dec +3.36°C/dec
LSZH Zürich Kloten 27.7 25.5 +2.2 32.1 +1.67°C/dec 0.00°C/dec
LTAC Ankara Esenboga 31.2 29.9 +1.3 35.0 +0.90°C/dec 0.00°C/dec
LTFM Istanbul Airport 32.7 31.0 +1.7 36.8 +2.50°C/dec +3.29°C/dec
LWSK Skopje Airport 36.3 32.4 +3.9 40.6 +3.33°C/dec +3.08°C/dec
LYBE Beograd Nikola Tesla 31.5 29.4 +2.1 36.4 +2.50°C/dec +0.93°C/dec
LYPG Podgorica Airport 36.1 33.2 +2.9 41.2 +4.43°C/dec +8.50°C/dec
LZIB Bratislava M. R. Štefánik 29.7 27.7 +2.0 33.1 +1.71°C/dec +0.75°C/dec
UUEE Moscow Sheremetyevo 24.0 24.5 -0.5 27.9 0.00°C/dec -1.43°C/dec

"Stale bias" = VN-1 minus the plain multi-decade mean for today's calendar day — the number a stale-normals model misprices by. An amber Q90 trend above the Q50 trend is the tail fattening faster than the mean.

Methodology — VN-1

  • Window: the last 15 completed years of finalized daily Tmax/Tmin (ISD + METAR), ±7-day day-of-year window (15-day centred, leap-stable).
  • Model: exact linear quantile regression (pinball loss, no regularization) of temperature on year — separately for q10/q50/q90 of Tmax and Tmin, so each quantile carries its own trend.
  • Output: the fit evaluated at the current year, plus trend slopes in °C/decade. Rows carry sample sizes; method changes version (VN-2, …) and are never applied silently.
  • Where it works: our degree-day settle projections use VN-1 beyond the ensemble horizon — the projection inherits the trend instead of a stale mean.

Use it

curl "https://voltcast.com/api/v1/normals"          # today, all stations
curl "https://voltcast.com/api/v1/normals/LFPB"     # full-year curve, Paris-Le Bourget

Keyless and CORS-open. The station-exact forecast distributions, settle projections and degree-day trackers built on top live in Volt Temp (€99/mo) and on the Desk.